Single-Cylinder Engine Evaluation of Methanol - Improved Energy Economy and Reduced NOx 750119
Comparative testing of pure methanol, methanol/water blends and isooctane in single-cylinder engines has demonstrated that through proper utilization of methanol's fuel-lean combustion characteristics it may be possible to reach CO emissions of the order of 0.1 percent and NOx emission levels of less than 100 ppm in the raw (undiluted) exhaust. Exhaust treatment to remove unburned methanol and partial oxidation products might be required. Concomitant with decreased emissions are specific energy consumption improvements estimated to be in the range of 26 to 45 percent better than achievable with current gasolines and the associated low compression ratio engines and emission control systems. These energy consumption improvements are obtained by virtue of efficient lean operation and by utilizing the high octane values of methanol/water blends at high compression ratios. Despite these potential end-use technical advantages for methanol, its large scale use as an automotive fuel is precluded for at least one to two decades because of inadequate supply, the need for immense capital expenditures to increase supply and the need for special engine and fuel control designs.